From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 891B8C4360C for ; Thu, 26 Sep 2019 14:22:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5B01D222C7 for ; Thu, 26 Sep 2019 14:22:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726990AbfIZOWl (ORCPT ); Thu, 26 Sep 2019 10:22:41 -0400 Received: from mx1.redhat.com ([209.132.183.28]:50864 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726500AbfIZOWl (ORCPT ); Thu, 26 Sep 2019 10:22:41 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 7BACA30089A1; Thu, 26 Sep 2019 14:22:41 +0000 (UTC) Received: from localhost (unknown [10.40.205.151]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 10C1E5D6B0; Thu, 26 Sep 2019 14:22:40 +0000 (UTC) From: Max Reitz To: linux-xfs@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Max Reitz , "Darrick J . Wong" , Brian Foster Subject: [PATCH] xfs: Fix tail rounding in xfs_alloc_file_space() Date: Thu, 26 Sep 2019 16:22:38 +0200 Message-Id: <20190926142238.26973-1-mreitz@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.46]); Thu, 26 Sep 2019 14:22:41 +0000 (UTC) Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org To ensure that all blocks touched by the range [offset, offset + count) are allocated, we need to calculate the block count from the difference of the range end (rounded up) and the range start (rounded down). Before this patch, we just round up the byte count, which may lead to unaligned ranges not being fully allocated: $ touch test_file $ block_size=$(stat -fc '%S' test_file) $ fallocate -o $((block_size / 2)) -l $block_size test_file $ xfs_bmap test_file test_file: 0: [0..7]: 1396264..1396271 1: [8..15]: hole There should not be a hole there. Instead, the first two blocks should be fully allocated. With this patch applied, the result is something like this: $ touch test_file $ block_size=$(stat -fc '%S' test_file) $ fallocate -o $((block_size / 2)) -l $block_size test_file $ xfs_bmap test_file test_file: 0: [0..15]: 11024..11039 Signed-off-by: Max Reitz --- fs/xfs/xfs_bmap_util.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c index 0910cb75b65d..4f443703065e 100644 --- a/fs/xfs/xfs_bmap_util.c +++ b/fs/xfs/xfs_bmap_util.c @@ -864,6 +864,7 @@ xfs_alloc_file_space( xfs_filblks_t allocatesize_fsb; xfs_extlen_t extsz, temp; xfs_fileoff_t startoffset_fsb; + xfs_fileoff_t endoffset_fsb; int nimaps; int quota_flag; int rt; @@ -891,7 +892,8 @@ xfs_alloc_file_space( imapp = &imaps[0]; nimaps = 1; startoffset_fsb = XFS_B_TO_FSBT(mp, offset); - allocatesize_fsb = XFS_B_TO_FSB(mp, count); + endoffset_fsb = XFS_B_TO_FSB(mp, offset + count); + allocatesize_fsb = endoffset_fsb - startoffset_fsb; /* * Allocate file space until done or until there is an error -- 2.23.0